STM32F4 Discovery board - Keil 5 IDE with CubeMX: Tutorial 8 UART - Updated Dec 2017

[@faisal-ok1yp]

May Allah(SWT) reward you brother! This helped me to land an internship.

[@mutexembedded2206]

Thank you bro. Glad to hear!

[@WarrenD77]

AHHHHHHHHHHHH THIS IS THE ONLY THING I'VE GOTTEN TO WORK IN WEEKS, TYTYTYTY!

[@Tony770jr]

Though you might have increased the editor font, I was trying to watch on my laptop, but the black background and the text colors produce poor contrast, had to stop viewing. :-(

[@roderickdiaz3834]

compiling stm32f4xx_hal.c... compiling stm32f4xx_hal_tim.c... "uart_video\uart_video.axf" - 4 Error(s), 1 Warning(s). Target not created. Build Time Elapsed: 00:01:53 why this errors help me please im newbie

[@roderickdiaz3834]

*** Using Compiler 'V5.06 update 6 (build 750)', folder: 'C:\Keil_v5\ARM\ARMCC\Bin' Build target 'uart_video' compiling main.c... ../Src/main.c(114): error: #20: identifier "unit8_t" is undefined HAL_UART_Transmit(&huart2,(unit8_t *)txData,strlen(txData),10); ../Src/main.c(114): error: #29: expected an expression HAL_UART_Transmit(&huart2,(unit8_t *)txData,strlen(txData),10); ../Src/main.c(114): error: #165: too few arguments in function call HAL_UART_Transmit(&huart2,(unit8_t *)txData,strlen(txData),10); ../Src/main.c(114): error: #18: expected a ")" HAL_UART_Transmit(&huart2,(unit8_t *)txData,strlen(txData),10); ../Src/main.c(103): warning: #177-D: variable "txData" was declared but never referenced char txData[30] = "Hola Trols "; ../Src/main.c: 1 warning, 4 errors "uart_video\uart_video.axf" - 4 Error(s), 1 Warning(s). Target not created. Build Time Elapsed: 00:00:06

[@mutexembedded2206]

Hi, One of the errors is a typing error, it is uint8_t instead of unit8_t

[@shoes7973]

Great Job Mohammed. Nice video and very well explained. I hope you wont mind if I point out that the volume on your videos is pretty low. Quite a strain to hear and follow without good speakers or headphones. please look into it if you can find the time. Regardless, thank you for your efforts and keep up the good work.

[@mutexembedded2206]

Hello, Thanks mate! Do you think all the videos have a low sound volume or just this one ?

[@VishalVerma-sz2zu]

all the videos sir

[@samineni100]

HI doesn't this discovery board support USART over the virtual com port? is it required to get a usb to ttl converter?

[@mutexembedded2206]

No, you either do some jumper wires or use bridge. Look at page 13: www.st.com/resource/en/user_manual/dm00039084-discovery-kit-with-stm32f407vg-mcu-stmicroelectronics.pdf

[@furydonnico]

Is it possible to enable DMA on Half-Duplex receive only with USART2 ? The pin use in that case is PD5 (USART2_TX) but DMA parameters within CubeMX only concern USART2_RX

[@mutexembedded2206]

I think so

[@DanhNguyen-qc2xt]

Can you help me with this? My Realterm application waited until I put 2 lines of string or more than that to return the string. And no matter how many the repeats of string, it returned only 2 line of the string. I don't know much about this, perhaps my board has some problems?

[@mutexembedded2206]

Try using TeraTerm

[@Andrew_EvsW]

Very nice video with a great explanation .

[@emreozturk8842]

Hi uart listened to your lesson. I have a gsm module and I want to see the OK response on the terminal when I send AT command. How should I set up an algorithm for this?

[@mutexembedded2206]

Good one.. worth a tutorial in its own

[@nikolamitrovic3642]

@@mutexembedded2206 Hello, Thank you very much for your effort and contribution. Your tutorials are outstanding! I would like to know if this specific question was further analyzed? I am trying to interface ESP8266 with STM32 through AT commands, and algorithm for AT commands communication would be highly appreciated :) I succesfully went through the first stage AT>OK, but I get counfused when it comes to complicated commands, probably my logic isn't good. Thanks in advance Best Regards

[@kemalcihanbastak8476]

Hey MYaqoob thx for these tutorials My question is I don’t have usb to serial converter. Instead can I do it with an Arduino Uno board by bypassing the chip and use the serial converter on the arduino board as usb to serail converter?

[@mutexembedded2206]

Yes in fact you just need to connect to tx0 and rx0 on Arduino and it will show up on PC

[@jesuscarrionserrano1630]

Im trying doing this with a stm32f4-discovery, and when i open realTerm, nothing happens, there isn't any hello world in the black screen but the status of "Ring", "CTS" and "DSR" are blinking in green. Any solution ???

[@rakesh231rakesh]

These tutorials are great. I just wondering, why to use DMA over Rx interrupt! DMA interrupts on data received of fixed length. Simply, should use the UART Rx interrupt. There is no guarantee that data received on UART will be of fix length in real world uses.

[@seferideveloper6933]

I agree with you

[@hamzafodil7089]

Hi Bro, Do the companies (where you are living) use CubMx, HAL_Drivers or Registers programming (CMSIS Core) ???? Please, I need your answer?

[@mutexembedded2206]

Hi, Use all together

[@dharmikbhavani7272]

First, thank you for this extremely helpful series. But have dought in mind what to do if receiving bytes are not the same or let say unknown then what about DMA interrupts let say having Rx pin connected to GSM or RS485 each time byte length will be different what to do. Is there any way to generate interrupt after compleat RX event is done.

[@seferideveloper6933]

Did you find the answer bro ?

[@DARKVEEMON1]

Hi, is it possible to use a HC-05 Bluetooth module instead of the USB?

[@talhajaved2586]

I am using STM32F407VGTx. When I am sending data from board to PC it is receiving perfectly fine. But when it comes to receiving data from PC to board the variable of board is not receiving any data. Kindly help me.

[@alibarakat1056]

Salam Alaikom dear Mohammad I appreciate your work and I consider you as my teacher of programming STM32 microcontrollers... I need something please, a tutorial of using USART RxTx in interrupt mode and in DMA .... Another thing I need is to know when the CallBack function is called? What time I mean? What is its role ? Thanks a lot

[@germanvelardez7947]

Why use HAL_UART_RxCpltCallBack function without using HAL_UART_Receive_IT() function, shouldn't you use function UART_DMAReceiveCplt(); instead the other one?

[@kavyav334]

Hi have a doubt Can we enable two UART at a time nd connect one to pc another to nextion display is it possible?

[@hero21number18]

why did you leave hal_uart_transmit function in the while loop

[@naasikhendricks1501]

Asalaamu Alayakum, I was wondering if you can tackle a more complex example ie using a DMA interrupt....? Just a question. If you can would you able to point me to a source that I am able to reference. Kind regards. Your videos really got me going! Keep it up!

[@ahmetemin08]

Please share project files completely. I can't get it work

[@AnbuArasan-tj8bc]

Thanks a lot for making this series..Is there anyway i can convert my project files from one ST series board to other ST series using STCubemx

[@mutexembedded2206]

Easiest way is to modify generated code: kzbin.info/www/bejne/j4aXm5ysir99o5o Or manually copy peripheral settings on CubeMX. Cannot think of an automatic way to do this.

[@zuhaibchoudhary4635]

I cant understand what is The use Of DMA ? Also what If I want to send HELLO then I want to receive HOW ARE YOU in return.What Will I have to do for it.

[@mutexembedded2206]

DMA allows us uninterrupted receive operation. To receive something, there many different structures, the simplest one I think is to open DMA receive in circular mode and check DMA count periodically for valid data.

[@zuhaibchoudhary4635]

What will I have to look into If I have to Custom send and custom receive using USART like I said If I send HELLO I should get HOW ARE YOU in retur.

[@zuhaibchoudhary4635]

There are three ways we can use USART 1.POLLING 2.INTERRUPT 3.DMA Now I want to send Hello And I should get how are you in return . I have been trying it from like hour cant do it please guide.

[@mutexembedded2206]

@@zuhaibchoudhary4635 Watch this: kzbin.info/www/bejne/ZomwhGtsl8mte9E

[@machirelax9746]

Iam trying to do UART transmission every 5 minutes using Timer. Could you please help me with how to use timers for UART transmission

[@diegoriquelme7935]

Dear Mohamed, it is nice to greet you at the same time thanking you for your contribution to the use of the STM32F4 Discovery board and Keil 5 IDE with CubeMX ... Since everything is very interesting and would like to ask you if it is possible that the tutorials could be activated the function of language translation to make it easier to interpret each and every one of the explanations that you provide for those They do not handle the same language perfectly. This is simply a request if it is possible that you could apply it. I greet him cordially and again thank him for all his contribution to the subject. keep in touch. hug! Diego from Argentina

[@mutexembedded2206]

Hi Diego, Thanks for that, great to know that people like yourself found this helpful. I don't know how to activate the Language translation at the moment, I will try find out. And sure will do my best to get that ON. Thanks again :)

[@diegoriquelme7935]

many thanks! you are very kind ... go ahead with the tutorials that are of great importance. thanks to you, really! regards!!!

[@shadabahmad1051]

Sir,I have tried what u did in the video,everything same ....but still nothing is showing in realterm teminal

[@lilbrothaaa]

Did you install the driver for your USB-TTL adapter?

[@dineshsundarschannel5317]

@@lilbrothaaa Thank you sir. its helped me www.instructables.com/id/Usb-to-SerialTTL-adapter/

[@Yassin_Ro]

Great Video Bro😊 Can you tell me please how can I delete the received data from Rx_buffer (UART interrupt) in order to receive new data from Rx_buffer[0] ?

[@mutexembedded2206]

Hi, Use memset(array, 10, 0)

[@abdmorioglu4868]

hello can ı make this controller commuinicate with my plc wich had modbus port or if it had ethercat op ethernet port

[@mutexembedded2206]

Yes very easy

[@CmZam17]

Thank's for the nice tutorial. MYaqoob!.

[@shahidkhan-md3dw]

Sir,tell me about cubeMx in stm32

[@LeonardoSilva-yj9lg]

could help me simulate rx tx reading on proteus?

[@siva-xd1bl]

hi, how could i send decimal point/floating numbers through uart

[@gunitsingh2978]

convert float to char and then send and at receiver do char to float back

[@dineshsundarschannel5317]

Thank you very much dear MYaqoobEmbedded . its helps me lot

[@dineshsundarschannel5317]

link to download adapter driver: www.instructables.com/id/Usb-to-SerialTTL-adapter/ and follow the instructions

[@entangleer]

@MYaqoobEmbedded Hi, HAL_UART_RECEIVE_DMA(-----) ; This part of code is not in while loop so how it receives the data continuously and rxCpltCallback function is called. Does the DMA_CIRCULER mode is doing this means receiving the data continuously.

[@mutexembedded2206]

Hi, I suggest you read about DMA. It is not hard

[@entangleer]

@@mutexembedded2206 Ok, can you suggest any resources about DMA regarding the embedded/stm32. Because I have already learnt about DMA in computer organisation and architecture subject.

[@mutexembedded2206]

@@entangleer STM32 has DMA as AHB bus master. In a sense it acts like a cpu in terms of access to system memory. Thus, when DMA is running it's more like another parallel code in background, so it doesn't need to be in the main loop and so on. You can read a full article by ST on Google.

[@VishalVerma-sz2zu]

Hey, Great video! Would you please consider posting a tutorial on how to implement the DCMI and I2S on this board. Warm Regards, Vishal India

[@hectoreliucaballerodimas6752]

Nice video Have you tried this to conect de usart 2 to the stlink V2? I'm trying but i don't know if its a driver problem or what but in the serial i just don't see anything this is how it looks www.st.com/content/ccc/resource/technical/document/user_manual/70/fe/4a/3f/e7/e1/4f/7d/DM00039084.pdf/files/DM00039084.pdf/jcr:content/translations/en.DM00039084.pdf

[@mutexembedded2206]

Hi, yes, ST-LINK UART for the board requires physical wiring: Same as your link on page 13

[@bhuvaneshs.k638]

Please do USART

[@JairoGustavo]

thanks for the video!

[@1luvUrahara]

Thank you so much

[@tonyzhu4571]

circular, got it.

[@design4682]

tooooooooooooooooooooooooooooooooooo fast to understand

[@zuhaibchoudhary4635]

what is the function for buffer clear DMA clear

[@mutexembedded2206]

Hi, DMA is low level memory interface, it doesn't quite implement a buffer like stream libraries. It writes straight to a user specified memory. The clear sense here is you stop dma and perhaps set your memory to all 0s or something like that.